Photographic camera



4 Sheets-Sheet 1 IN v ENTOR:

RY WRDDINGTQH FITTORNEI D. G. H. WADDINGTON PHOTOGRAPHIC CAMERA FiledJuly 8, 193:;

Dawn GEORGE HEN May 27, 1941'.

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PHOTOGRAPHIC CAMERA Filed July 8, 1938 4 Sheets-Sheet 2 INVENTORL DHVIDGEORGE HENRY WHOEuNCvToN /Z on FITTORNEY PHOTOGRAPHIC CAMERA Filed July8, 1938 4 Sheets-Sheet 3 IN vswron: Dnvm GEORGE Hzrmy wnonmerofl ax/CW2?6. 6

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PHOTOGRAPHIC CAMERA Filed July 8, 1938 4 Sheets-Sheet 4 INVENTOR'. DnvmG'EoRQrE Ham wnoomevrou HTTORNBY Patented May 27, 1941 PHOTOGRAPHICCAMERA David George Henry Waddington, Bournemouth, England ApplicationJuly -8, 1938, Serial No. 218,059 In Great Britain November 9, 1937 4Claims.

The invention relates to photographic cameras of the type adapted tomake a plurality of exposures each through a separate color filter inassociation with a sensitive plate to produce images which aresubsequently superimposed to give a color rendering of the subject.

More particularly the invention relates to cameras of the above kind andhaving a repeating back, 1. e. one in which the back is enlarged toaccommodate a dark slide adapted to be moved step by step past anaperture in the back of the camera and having in association a pluralityof color filters or screens one for each position so that the individualsensitive plates, films or the like positioned in the dark slide areexposed successively through its associated color screen. It will ofcourse be appreciated that a single plate, film or the like may be usedin which case only a part will be exposed each time.

Apparatus of this kind is already known but the known constructions haveseveral disadvantages. In the first place to get the best results itmust be possible to set with a fine degree of accuracy the individualexposures in order to secure the necessary ratio between the variousexposures according to the characteristics of the particular plate orfilm and its associated color filter. Hitherto where the smallest timeadjustment obtainable was A second some attempt has been made to securea more accurate ratio by lengthening the time of the individualexposures.

Such apparatus, however, while giving fairly satisfactory results withstill life subjects where the object to be photographed is stationary,is unsuitable for objects which are liable to movement owing to the timenecessary in moving each plate or part of a plate (when one large plateis used to take all exposures) into register with the aperture in theback of the camera.

It will also be readily understood that considerable skill is necessaryin making such adjustments and once set it could not be assumed that theratio would remain the same over any appreciable period of time.

The object of the present invention is to provide an apparatus of theabove general type which shall be entirely automatic in its actionwherein difierences in length of each exposure due to the particularplate or filter employed can be easily provided for, wherein the lengthof time required for the exposing of the various plates can be reducedto a minimum, a very desirable proviso in taking portraits or othersubjects liable to movement during the various exposures and alsowherein the ratio selected will remain substantially constant.

With the foregoing objects in view, the present invention provides arepeating back camera for use in color photography comprising adark-slide carrier, color differentiating light filters operativelyassociated with said dark-slide carrier, a detachable andinterchangeable roller blind shutter, said shutter having a plurality ofapertures, each aperture being of fixed size proportioned according tothe exposure required to be given thereby as determined by the color ofthe filter employed and the color sensitivity of the make of plate orfilm employed, tensioning means for moving said dark-slide carrier,tensioning means for moving said roller blind shutter, pinion, rack,cam, tappet and stop mechanism for interrupting the movement of saiddark-slide carrier so that said dark-slide carrier and said shutter bothmake step-by-step movements, the movements of one alternating with themovements of the other, whereby plates or films for successive colorseparation negatives are exposed through successive apertures, mechanismfor resetting said dark-slide carrier and said shutter, means forholding said dark-slide carrier and said shutter in the set position,and means for releasing same.

The shutter may operate automatically by means of a small clockwork orother motor or by an initial hand movement, or by any other suitablemeans, while the same movement may also give the desired periodicmovement to' the color filters which may be placed either in front of orbehind the shutter or may be contained in the dark-slide in front of theplates or in the carrier for the dark-slide.

The roller blind is preferably mounted on two transversely disposedrollers having their axes in fixed relation to the camera.

The color filters which are preferably formed of sheets of stainedgelatine in the usual way are adapted to move in unison with themovement of the dark-slide containing the light sensitive plates and maybe disposed either to the front or the rear of the roller blind shutter,and may be moved or operated as already mentioned by the mechanism whichoperates the roller blind shutter.

The camera may be so constructed that the carrier for the dark slide andshutter are directly and dependently operable through the intermediaryof mechanism which permits of each being released and stoppedalternately and successively. In one construction to efieot themovereached certain predetermined points one of 1 these projectionscauses pins or other stops to be withdrawn to allow the movement ofother mechanism to give a corresponding movement to the dark-slide andcause the dark-slide to be moved to bring the next succeeding plate intoalignment with the aperture in the rear of the camera whilst at the sametime the next desired color filter is moved into position to take afurther exposure on another plate and through that filter. Anotherprojection will engage stops which control the movement of the rackitself, and the mechanism operating the roller blind shutter.

The elongated back of the camera already referred to may be soconstructed as to permit the dark-slide to be moved into the variouspositions necessary to bring each plate into alignment with the openingin the back to take the exposure. The dark-slide or the carrier for samemay travel across the back in rails or guides or by other suitable meansand may be propelled by clockwork or other motor or by initialhandmovement or by any other suitable means.

In order that the invention may be more clearly understood referencewill now be made to the accompanying drawings wherein:

Fig. l is a rear elevation of the back of a camera.

Fig. 2 is a front elevation of the camera back shown in Fig. 1

Fig. 3 is a plan of the camera back shown in Fig. 1.

Figs. 4 and 5 are respectively sections along lines 4-4 and 5-5, Fig. 3,looking in the direction of the arrows.

Fig. 6 is a part plan broken away, illustrating the rack and tappetmechanism.

Fig. 7 is an elevation on a reduced scale, broken away, illustrating thecarrier.

Fig. 8 a part elevation illustrating the carrier.

Fig. 9 is a perspective view on a reduced scale illustrating the camera.

Fig. 10 illustrates a modification of detail.

In the form shown in the drawings the camera back 2 is formed with acentral aperture 3 and is provided with grooves 4 to receive adark-slide carrier 5, which is provided with three light filters 5 5 5in front and with distinguishing marks e. g. x, y, z to indicate thecorrect color plates. Rails and antifriction rollers (not shown) may beincorporated to ensure a free movement of the carrier 5. Within the back2 are mounted the roller blind rollers 6 and l carrying the roller blindshutter 8. The spindle of'the roller 6 passes through the top of theback 2 and is provided with a pinion 9 which is engaged by a rack Itslidably mounted in a rack groove ll formed along the top of theplatform Ho. The rack H] is retained in the rack groove H by a bracket12. The rack it which is square cut is provided at its forward end,which is square cut, with a cam M mounted on top thereof. Rotation ofthe blind roller 6 is therefore controlled by the rack it the rollerblind tensioning device tending to urge the rack forward along thegroove ii. The tensioning and winding mechanism for the roller blindshutter 8 comprises a clockwork motor l3 driven by a spring [5 andcoupled by a kind of universal joint IE to the spindle ll of the shutterroller 1 for working said roller, the join it allowing a certain amountof play.

For re-setting the shutter a cord 58 and a pulley 19 are provided, thepulley It being con.- nected by a kind of universal joint 22 to thespindle 26a of the roller E5.

Assuming the cord l8 fully wound on the pulley it when cord i8 is pulledit rotates the pulley IS and resets the shutter 8, and at the same timerotating roller 7. The rotation of the roller 1 during resetting of theshutter 8 winds up the clockwork motor is.

Slidably mounted on the platform Ha and passing through the back 2 in adirection transverse to the rack I 0 are tappets 25, 22, 23 and 24arranged in pairs. One end of each of the tappets El and 23 arepositioned to be engaged by the cam l5 whilst one end of each of thetappets 22 and 24 are positioned to be engaged by the square forward endlea of the rack Ill. The other end of each of the tappets 2|, 22 and 24are turned downwardly to form stops 25, 25 and 2'! respectively whilstthe other end of the tappet 23 is turned up to engage a stop lever 28pivoted to a bracket 29 mounted on the top 2a of the back 2. All thetappets are urged inwardly towards the rack I0, suitable stops beingprovided to limit such movement.

The top of the dark-slide carrier 5 is provided with a front cam 35, arear cam 35, a front stop 31 and a rear stop 38. The carrier 5 is urgedalong its track by a cord 39 connected at its other end to the drum 4-9of a tensioning dcvicc after passing over suitable guide pulley 4!.

Also mounted on top of the back 2 are guides 59 for a setting stop 5|adapted to hold the rack ll] in the set position and to be manuallyoperated to release the mechanism.

The operation of the device is as follows. The roller blind shutter iswound on to the roller t until the rack It has moved far enough for thefront end to be engaged by the setting stop 5| and is held thereby. Thedark-slide carrier is then moved along its track in the same direc tionuntil the front stop 3'! thereon passes and engages with the stop 25 onthe tappet 2|. The dark-slide loaded with plates or films each with itsassociated color filter is then fixed in the carrier 5 and the slidewithdrawn. The camera is now loaded and set. I

On withdrawing the stop 51 the rack I!) is released allowing the shutterto unroll and expose the first plate. Immediately the aperture in theshutter has passed the aperture 3 in the back of the camera the cam l4on the rack IE] engages th tappet 2! moving the stop 25 out of the pathof the stop 3'! thereby releasing the carrier 5. Further movement of therack l0 after releasing the carrier 5 is prevented by the forward endengaging the tappet 22.

Immediately on being released the carrier 5 4' moves rapidly to thesecond position in which the rear stop 38 abuts against the stop 28a onunderside of the pivoted lever 28. Just before this position is reachedthe front cam engages the stop 26 on tappet 22 again releasing the rackI0 to start the second movement of the roller blind shutter and exposethe second plate.

The action of the mechanism during the second stage is very similar tothe first. Immediately the second exposure has been made the cam Hengages the tappet 23 which moves the stop 28 out of the path of thestop 38 and further movement of the rack I is prevented by contact withthe tappet 24.

Th carrier then moves to its third and final position at the end of itstravel and just before reaching the end the rear cam 36 coacts with thestop 21 withdrawing the tappet 24 from out of the path of the rack l0and releasing the shutter for the final exposure.

It will be obvious that the device can be modified without departingfrom the scope of the invention for example the filter screens may bemounted in an outer metal frame or between optical plates or otherwise.The roller blind shutter may be formed in, sections flexibly connectedone to the other as may be desired. The material of the shutter may befabric, metalised, rubberised or otherwise, or thin metal plates may beused.

It will be understood that the length of apertures in the shutter can bevaried according to the characteristics of the filters and also of anyparticular make of plate employed and various other modifications may bemade in the construction hereinbefore referred to in the scope of theappended claims.

As illustrated in Fig. modified means may be provided for turning theroller 1 and such modified means may comprise a spring loaded roller 52(similar to an ordinary blind roller) with a tensioning device 53, 54,55 and a calibrated scale 56 and pointer 51 to indicate the state of thetension.

With a device made according to this invention the movements of theshutter and dark-slide carrier are automatic and interdependent. Theshutter apertures are predetermined and therefor the ratios of theexposures are substantially fixed irrespective of the speed of theshutter so that the balance of the exposure is assured, thus eliminatingthe loss of balance which is one of the chief causes of so many failuresand disappointments.

What I claim and desire to secure by Letters Patent is:

1. A repeating back camera for use in color photography comprising trackmeans for receiving a dark-slide carrier, a dark-slide carrier providedwith colour difi'erentiating means, roller blind rollers carrying aroller blind shutter having exposure proportioned apertures, a. pinioncarried by one of said rollers and engaged by a rack slidably mounted onthe top of the platform, a cam device on said rack, tensioning andwinding mechanism for the roller blind, means for resetting the shutterand for winding up the motor, movable tappet means for engaging said camdevice, movable tappet means for engaging said rack, stop movable tappetmeans, a stop lever device pivotally connected to the camera back, meanscarried by said tappet means to engage said lever device, means carriedby the darkslide carrier for engaging said tappet means, means forholding the rack in the set position and for releasing the mechanism.

2. A repeating back camera for use in color photography comprising acentrally apertured back, track means for receiving a dark-slidecarrier, a dark-slide carrier provided with light filters Within theback, roller blind rollers carrying a roller blind shutter havingexposure proportioned apertures, a spindle to one of said rollerspassing through the top of the back and provided with a pinion engagedby a rack slidably mounted in a rack groove formed along the top of thplatform, means for retaining said rack in the groove, a cam on saidrack, tensioning and winding motor mechanism for the roller blind, meansfor resetting the shutter and for winding up the motor, tappet means forengaging said cam, tappet means for engaging the forward end of therack, stop tappet means, a stop lever device pivoted to a bracket on thetop of the camera back, means carried by said tappet means to engagesaid lever device, said tappet means having a movement towards saidrack, means carried by the top of the dark-slide carrier for engagingsaid tappet means urging the carrier along its track, means for holdingthe rack in the set position and for releasing the mechanism.

3. A repeating back camera for use in color photography comprising acentrally apertured back, track means for receiving a dark-slidecarrier, a dark-slide carrier provided with light filters and means forindicating the correct color plates, within the back roller blindrollers, carrying a roller blind shutter having exposure proportionedapertures, a spindle to one of said rollers passing through the top ofthe rack and provided with a pinion engaged by a square cut rackslidably mounted in a rack groove formed along the top of the platformand retained in the groove by a bracket, a cam on the forward end ofsaid rack, tensioning and winding motor mechanism for the roller blind,means for resetting the shutter and for Winding up the motor, slidablymounted on the platform and passing through the back in a directiontransverse to the rack pairs of tappets, means carried by some of saidtappets for engaging said cam, means carried by some of said tappets forengaging the forward end of the rack, stop means carried by some of.said tappets, a stop lever pivoted to a bracket on the top of the cameraback, means carried by one of said tappets to engage said lever, saidtappets having a limited inwardly urged movement towards said rack, camscarried by the top of the dark-slide carrier for engaging said tappets,means for urging the carrier along its track, means for holding the rackin the set position and means for manually releasing the mechanism.

4. A repeating back camera for use in color photography comprising acentrally apertured back, grooved members to receive a dark-slidecarrier having three light filters in front and distinguishing marks toindicate the correct colour plates, within the back two roller blindroller-s carrying a roller blind shutter, said shutter having aplurality of apertures, each aperture being proportioned according tothe exposure required to be given thereby as determined by the color ofthe filter employed and the color sensitivity of the plate employed, aspindle to one of said rollers passing through the top of the back andprovided with a pinion, a square cut rack engaged by said pinion andslidably mounted in a rack groove formed along the top of a platform, abracket retaining said rack in said groove, a cam mounted on top of saidrack, tensioning mechanism to said roller blind, to urge the rackforward along the groove, winding mechanism to said blind, saidmechanism including a clockwork motor driven by a spring, and coupled bya kind of universal joint allowing play with the spindle of the shutterroller for working said roller, a cord and a pulley for resetting theshutter, a kind of universal joint connecting said pulley to the spindleof the roller, so that the rotation of the roller during resetting ofthe shutter winds up the motor, two pairs of tappets slidably mounted onthe platform and passing through the back in a direction transversetothe rack, one end of one of. each pair of tappets being positioned tobe engaged by the cam, and one end of the other of each pair of tappetsbeing positioned to be engaged by the square forward end of the rack,the remaining end of one of the first-mentioned tappets and of each ofthe second-mentioned tappets being turned downwardly to form a stop,whilst the remaining end of the other of the first-mentioned tappets isturned up to engage a stop lever pivoted to a bracket mounted on the topof the back, all the tappets being positioned to be urged inwardlytowards the rack, suitable stops for limiting such movement, on the topof the dark-slide carrier for engaging said tappets a front cam, a rearcam, a front stop and a rear stop, a tensioning device provided with adrum, a cord attached at one end to said drum and passing over a guidepulley to urge the carrier along its track, on the top of the backguides holding a setting stop to hold the rack in the set position andto be manually operated to release the mechanism.

DAVID GEORGE HENRY 'WADDINGTON.

